THURSDAY, June 2, 2016 (HealthDay News) -- The number of babies born to American teenaged girls fell another 8 percent in 2015, reaching a new record low.

According to the report from the U.S. Centers for Disease Control and Prevention, moms aged 15 to 19 accounted for about 22 of every 1,000 live births in 2015 -- down from about 24 per 1,000 the year before.

Dr. Jennifer Wu, an obstetrician-gynecologist at Lenox Hill Hospital in New York City, applauded the news.

"Most teenagers are not financially or emotionally equipped to be mothers at this point in their lives," said Wu.

"Teenage pregnancies present a myriad of social, medical and economic problems," she added, and "most of these pregnancies are unplanned and these mothers miss out on important aspects of prenatal care."

Overall, the report from the CDC's National Center for Health Statistics saw a continuance of a trend in which American women are having children later in life. Birth rates were also down for women in their early and late 20s, the report found -- but were rising for women in their 30s and 40s.

About 40 percent of births in 2015 occurred among unmarried women, a number unchanged from the previous year.

The news was mixed when it came the rate of healthy deliveries.

For example, the rate of preterm births rose slightly, to about 9.6 percent, the first such rise since 2007. The rate of babies being born underweight also edged up, from 8 percent in 2014 to close to 8.1 percent a year later.

However, the rate of cesarean deliveries -- which come with risks to mother and baby -- fell for the third year in a row, the CDC said. Just under one-third of deliveries are now done via C-section, the report found.

The report, published June 2, was based on nearly 100 percent of all birth certificates collected across the 50 states.